Modeling storage environments

ABSTRACT

Example embodiments provide various techniques for modeling network storage environments. To model a particular storage environment, component models that are associated with the components of the storage environment are loaded. Each component model is programmed to mathematically simulate one or more components of the storage environment. A system model is then composed from the component models and this system model is configured to simulate the storage environment.

RELATED APPLICATION

This application is a Continuation of U.S. patent application Ser. No.12/112,000, entitled “MODELING STORAGE ENVIRONMENTS”, filed Apr. 30,2008; the aforementioned priority application being hereby incorporatedby reference in its entirety for all purposes.

FIELD

The present disclosure relates generally to computer modeling. In anexample embodiment, the disclosure relates to the modeling of storageenvironments.

BACKGROUND

A storage environment can be a complex system because of the numerouscomponents included in the storage environment. Examples of componentsmay include network pipes, caches, storage servers, switches, storagecontrollers, and other components. As a result, the maintenance anddesign of such a complex storage environment are time-consuming tasks.For example, administrators currently troubleshoot problems of adeployed storage environment manually. The manual process oftroubleshooting the storage environment can be labor intensive and timeconsuming. Further, the process of troubleshooting the storageenvironment may require the storage environment to be temporarilyshutdown, which therefore also renders software applications that relyon the storage environment inoperable.

SUMMARY

Generally, a computer model is a computer program that is programmed tomathematically simulate a variety of systems, such as natural systems,biological systems, and computer systems. Example embodiments of thepresent invention provide various techniques for modeling a storageenvironment. In general, a storage environment is a system of computingdevices and storage devices where data is stored on the storage devicessuch that the data can be made available to a variety of clientcomputing devices on a network. It should be appreciated that thestorage environment may include a variety of hardware and/or softwarecomponents, such as computers, memories, hard drives, operating systems,software applications, and other components.

To model a particular storage environment, component models associatedwith the components of the storage environment are loaded. Similar tothe system model of the storage environment, each component model isprogrammed to mathematically simulate one or more components of thestorage environment. A system model is then composed from the componentmodels. In effect, the system model is constructed from the componentmodels. In an example, the system model may be constructed by connectingthe component models with each other based on functional relationshipsbetween the component models. The structure of the composed system modelmay be in the form of or resemble a directed graph. Accordingly, thesystem model may be represented as a directed graph. In general, adirected graph includes nodes with lines and/or arrows connecting thenodes. The directed graph may therefore illustrate an architecture ofthe storage environment. It should be appreciated that the system modelmay also be depicted by a variety of other representations or diagrams.

With the system model, a simulated workload may then be applied to thesystem model and the directed graph (or other representations) may beused to illustrate the simulated impact of the simulated workload on thestorage environment. In effect, the directed graph can be used toillustrate the simulated behavior of a storage environment when, forexample, subjected to various workloads. As a result, for example, auser can use such impact information to analyze, troubleshoot, maintain,and/or design the storage environment.

BRIEF DESCRIPTION OF DRAWINGS

The present disclosure is illustrated by way of example and notlimitation in the figures of the accompanying drawings, in which likereferences indicate similar elements and in which:

FIG. 1 depicts a representation of a system model of a storageenvironment, in accordance with an example embodiment;

FIG. 2 depicts a simplified block diagram of a storage system analyticsmodule, in accordance with an example embodiment, included in computingdevice;

FIG. 3 depicts a flow diagram of a general overview of a method, inaccordance with an example embodiment, for modeling a storageenvironment;

FIG. 4 depicts a simplified block diagram of a storage environment, inaccordance with an example embodiment;

FIG. 5 depicts a simplified block diagram of another example of astorage environment and software applications associated with thestorage environment, in accordance with an example embodiment, that maybe modeled;

FIG. 6 depicts a flow diagram of detailed methods, in accordance with anexample embodiment, for modeling a storage environment;

FIG. 7 depicts a flow diagram of detailed methods, in accordance with anexample embodiment, for composing a system model from component models;

FIG. 8 depicts another directed graph representation of a system model,in accordance with an example embodiment; and

FIG. 9 depicts a simplified block diagram of a machine in the exampleform of a computing system within which a set of instructions, forcausing the machine to perform any one or more of the methodologiesdiscussed herein, may be executed.

DESCRIPTION OF EXAMPLE EMBODIMENTS

The description that follows includes illustrative systems, methods,techniques, instruction sequences, and computing machine programproducts that embody the present invention. In the followingdescription, for purposes of explanation, numerous specific details areset forth in order to provide an understanding of various embodiments ofthe inventive subject matter. It will be evident, however, to oneskilled in the art that embodiments of the inventive subject matter maybe practiced without these specific details. In general, well-knowninstruction instances, protocols, structures and techniques have notbeen shown in detail.

A computer model is a computer program that can be programmed tosimulate a variety of systems, such as computer systems. In an example,a computer model can be used to mathematically predict the behavior of asystem without access to the actual system that is being simulated. Ineffect, a computer model is actually a mathematical model carried out bya computing device, such as a computer. The mathematical model may beconstructed to find analytical solutions to various types of problems,such as prediction of weather and physics simulation.

In an example, a computer model can be used to predict the behavior of astorage environment. A storage environment is a system of computingdevices and storage devices where data is stored on the storage devicessuch that the data can be made available to a variety of clientcomputing devices on a network. As explained in more detail below, acomputer model of the storage environment may be constructed and thiscomputer model uses a mathematical model of the storage environment tomathematically analyze and/or simulate the storage environment. Suchsimulation may be used to facilitate the design and management ofstorage environments by allowing a user, for example, to assess and/ortest impacts of simulated workloads on computer models of the storageenvironments.

FIG. 1 depicts a representation of a system model 100 of a storageenvironment, in accordance with an example embodiment. In general, astorage environment is a system of computing devices and storage deviceswhere data is stored on the storage devices such that the data can bemade available to a variety of client computing devices on a network.The storage environment is network-based data storage and, as explainedin more detail below, the storage environment can utilize a Storage AreaNetwork (SAN) and/or a Network Attached Storage (NAS) device. The systemmodel 100 is a computer model that is configured to simulate a storageenvironment. In effect, system model 100 is a functional representationof the storage environment.

A storage environment is comprised of a variety of components. Asexplained in more detail below, the components of a storage environmentmay include software applications, hardware, and services. Thecomponents of a storage environment may be depicted by a variety ofrepresentations or diagrams. For example, as depicted in FIG. 1, eachcomponent of the storage environment may be represented as a node in thedirected graph of system model 100. Here, the directed graph of systemmodel 100 shows or defines the components of an example storageenvironment, such as storage devices 108, storage server 102, andclients 104. Additionally, the directed graph defines the functionalrelationships between the components of the storage environment witharrows between the components. It should be appreciated that a directedgraph (or digraph) is a graph whose edges are ordered pairs of nodes.That is, each edge can be followed from one node to another node. Anarrow or line that connects one node to another node may, for example,illustrate that the nodes are operatively associated with each other.The direction of the arrows may, for example, illustrate theinput/output of data between the nodes. In an example embodiment, thedirected graph is non-hierarchical such that the directed graph does notdepict a ranking of a node relative to another node. For example, FIG. 1does not define that a node representing, for example, storage server102, is ranked relative to nodes representing storage devices 108.Furthermore, each node in a directed graph may be functionally related(or connected) to multiple nodes.

In addition to representing the system model 100 of the storageenvironment with the directed graph, other representations may be usedto depict the components and functional relationships. Another exampleof a representation may include a mixed graph having directed andundirected edges. In still yet another example, the system model 100 maybe represented by a table that lists the components and the functionalrelationships between the components. Other example representationsinclude flowcharts, weighted graphs, map diagrams, and otherrepresentations.

The embodiments described herein provide the modeling of a storageenvironment. As will be explained in more detail below, to model thestorage environment, system model 100 of the storage environment isinitially composed. A representation (e.g., a directed graph) can thenbe constructed based on system model 100. Such a representation may beused to illustrate the simulated behavior of a storage environment when,for example, subjected to various simulated workloads.

FIG. 2 depicts a simplified block diagram of a storage system analyticsmodule 203, in accordance with an example embodiment, included incomputing device 202. The computing device 202 is configured to host orexecute the storage system analytics module 203. The computing device202 may be included in a storage environment (e.g., a client computingdevice in communication with a storage system) or a stand-alonecomputing device independent of the storage environment. The storagesystem analytics module 202 is configured to model a storageenvironment. As depicted in FIG. 2, storage system analytics module 202may include provisioning manager module 204, hypothetical analyzer model206, and library module 208. The provisioning manager module 204 andhypothetical analyzer model 206 are operatively associated with librarymodule 208. For example, provisioning manager module 204 andhypothetical analyzer module 206 are in communication with librarymodule 208. It should be appreciated that storage system analyticsmodule 203 may be deployed in a variety of computing devices. Forexample, computing device 202 may include a personal computer, a servercomputer or other computing devices.

The library module 208 is a data structure that is configured to storecomponent models 210. In general, a data structure provides context forthe organization of data. Examples of data structures include tables,arrays, linked lists, databases, and other data structures. A componentmodel 210 is configured to simulate one or more components associatedwith a storage environment. In effect, a component model 210 is afunctional representation of one or more components associated with astorage environment. Components may include hardware, software, and/orservices. The components may be included within a storage environment.Alternately, the components may be configured to work with orcommunicate with the storage environment. Examples of hardwarecomponents associated with a storage environment include storageservers, storage controllers, client computers, hard disk drives,optical disk drives, processors, random access memories, non-volatilememories, tape drives, controllers (e.g., Redundant Array of IndependentDisks (RAID) controllers), switches (e.g., Fibre Channel switches),adaptors (e.g., Storage Area Network (SAN) adaptors, Computer SystemInterface (SCSI) tape adaptors, network adaptors, and other adaptors),power supplies, network pipes, computer buses (Peripheral ComponentInterconnect (PCI) buses, SCSI buses, and other computer buses), andother hardware components. Examples of software components includeoperating systems, data replication software, data classification andmanagement software, device drivers, databases, volume managers, filesystems, multipathing software, backup and recovery software, antivirussoftware, networking software, data security or protection software,data search engines, file storage resource management software, dataretention software, system management software, performance software,end-user application software, and other software components.

In addition to component models 210 that simulate hardware and softwarecomponents of a storage environment, the component models may alsosimulate one or more services, in accordance to an example embodiment.Generally, a service is an act performed by a user. Examples of acts bya user include deploying software, accessing software, and a variety ofother acts. In effect, this component model may be a functionalrepresentation of a component associated with a service rendered by auser. A component model from component models 210 that simulates aservice may be defined by time. For example, a component model maydefine that a user may take fifty five minutes to deploy a software. Inanother example, a component model may define that a user may take threeminutes to login an operating system.

The component models 210 may be created by a user for use with storagesystem analytics module 203. For example, component models 210 may besupplied by the manufacturers of the hardware and software components.The component models 210 may include interfaces, code that simulates thecomponents, and rules. The creation of component models 210 may be basedon a set of common interfaces to create the system model. Generally, aninterface defines a communication boundary between components, such ashardware components, software components, and service components. Therules define, for example, standard methods or procedures. For example,a rule may prohibit one type of hardware component to be interfaced withanother type of hardware component. In another example, as explained inmore detail below, a rule may specify that component models 210 needparticular resources. The rules may also define the functionalrelationships between component models 210.

In an example embodiment, one or more component models 210 may alsoinclude an error associated with the component models. The error may bethe accuracy (e.g., as defined by a numerical value) associated with thesimulation of the component. For example, a component model configuredto simulate a NAS device may show that the NAS device is 90% utilized insimulation. However, in actuality, the NAS device is 60% utilized.Accordingly, an error of 30% may be associated with the component model.This error may then be used for correcting the component model duringsimulation.

The component models 210 are configured to be plugged into or storedwithin library module 208. As explained in more detail below, with agiven storage environment to be modeled, provisioning manager module 204may select a portion of component models 210 associated with the storageenvironment from library module 208. Provisioning manager module 204 canthen compose a system model from a portion of component models 210 thatis configured to simulate the storage environment. Hypothetical analyzermodule 206 may then apply one or more simulated workloads to the systemmodel to identify or define impacts on the storage environment.

It should be appreciated that in other example embodiments, storagesystem analytics module 203 may include fewer or more modules apart fromthose shown in FIG. 2. For example, provisioning manager module 204 maybe integrated with hypothetical analyzer module 206 to form one module.In another example, provisioning manager module 204 and hypotheticalanalyzer module 206 may be executed on computing device 202 whilelibrary module 208 may be hosted on a separate server.

FIG. 3 depicts a flow diagram of a general overview of a method 300, inaccordance with an example embodiment, for modeling a storageenvironment. In an example embodiment, method 300 may be implemented bystorage system analytics module 203 of FIG. 2 and employed in computingdevice 202. As depicted in FIG. 3, a storage environment to be modeledis defined at 302. A user or a software application may define thestorage environment to be modeled. The storage environment is comprisedof a variety of components and each component may be simulated by one ormore component models. At 304, the component models associated with thestorage environment are loaded. The loading of component models is totransfer the portion of the component models into the system model. Forexample, a library module may include a variety of component modelsassociated with a variety of storage environments. A portion of thecomponent models that are associated with the defined storageenvironment is transferred from the library module to a system model.

After the component models are loaded, the system model is composed fromthe component models at 306. In general, as explained in more detailbelow, the system model may be composed or constructed by associating(e.g., connecting) the component models with each other based onfunctional relationships between the component models. In an exampleembodiment, the structure of the composed system model may be in theform of or resemble a directed graph. Accordingly, the composed systemmodel can be represented by a directed graph that defines componentmodels and functional relationships between the component models. Inaddition to the directed graph, as discussed above, the component modelsmay also be depicted by a variety of other representations, such astables, flowcharts, and other representations.

One or more simulated workloads may then be applied to the system modelat 308. A simulated workload is a measure of processing performed by acomponent model and the application of the simulated workload is theassignment of the simulated workload to the component model. Assignmentof the simulated workload may include providing the simulated workloadas an input into the component model or defining the simulated workloadwithin the component model. For example, a simulated workload may definea number of files to be processed by the system model. Here, forexample, a component model simulating a storage server included in thesystem model may be assigned a number of files to be processed. Inanother example, the simulated workload may define a flow of data to aparticular component model included in the system model. Here, forexample, a component model may be assigned to receive 631kilobytes/second of data. In still another example, the simulatedworkload may be a ratio (e.g., ratio from 0 to 1) describing thecharacter of the loading of a component model.

The system model is configured to simulate an impact of the simulatedworkload on the storage environment. The impact is the effect of thesimulated workload. The impact of the simulated workload on the storageenvironment may be depicted or defined in a directed graph or otherrepresentations. In an example, the directed graph may show the behaviorof the storage environment under the simulated workload. As a result,for example, a user can use such impact information to troubleshoot thestorage environment. In another example, a user can use such impactinformation to design the storage environment. In yet another example, auser can use the impact information to assess the performance of a givenapplication that is designed to make use of the storage environment.

FIG. 4 depicts a simplified block diagram of a storage environment 400,in accordance with an example embodiment. It should be appreciated thata variety of storage environments may be modeled by the storage systemanalytics module. An example of storage environment 400 that may bemodeled is depicted in FIG. 4. The storage environment 400 includesclients 402, storage system 406, and storage devices 410. The storagesystem 406 is one or more computing devices that provide a storageservice related to the organization of information on writable,persistent storage devices 410, such as non-volatile memories, tapes,hard drives, optical media, and other storage devices. The storagesystem 406 can be deployed within a SAN environment or a NASenvironment.

When used within a NAS environment, for example, storage system 406 maybe embodied as a storage server that is configured to operate accordingto a client/server model of information delivery to thereby allowmultiple client computing devices (e.g., clients 402) to access sharedresources, such as files, stored on the storage server. The storage ofdata on a NAS environment can be deployed over a computer network thatincludes a geographically distributed collection on interconnectedcommunication links, such as Ethernet, that allow clients 402 toremotely access the data (e.g., files) on the storage server. Theclients 402 can communicate with the storage server by exchangingdiscrete frames or packets of data according to predefined protocols,such as Transmission Control/Internet Protocol (TCP/IP).

A SAN is a high-speed network that enables establishment of directconnections between storage system 406 and its storage devices 410. TheSAN may thus be viewed as an extension to a storage bus and, as such, anoperating system of storage system 406 enables access to stored datausing block-based access protocols over an extended bus. In thiscontext, the extended bus can be embodied as Fibre Channel, ComputerSystem Interface (SCSI), Internet SCSI (iSCSI), and other networktechnologies.

FIG. 5 depicts a simplified block diagram of another example of astorage environment 500 and software applications associated with thestorage environment, in accordance with an example embodiment, that maybe modeled. Components of storage environment 500 include storage server502 in communication with client computing devices 402. Storage server502 and client computing devices 402 may be in communication by way of anetwork, which may include one or more Local Area Networks (LANs) and/orWide Area Networks (WANs), such as the Internet. The Internet is anexample of a WAN that connects disparate networks to providecommunication between points on various networks. The points communicateby exchanging discrete frames or packets of data according topre-defined protocols, such as Transmission Control Protocol/InternetProtocol (TCP/IP). It should be appreciated that various protocols canbe used to transmit storage data over TCP/IP, such as iSCSI, NFS, CIFS,and other protocols. In the example illustrated in FIG. 5, storageserver 502 also is in communication with storage devices 208 (e.g., harddisks and tapes).

The client computing devices 402 may access various services andfunctions supported by storage server 502. Generally, storage server 502is a computing device that provides file services relating to thestorage, organization, and access of data stored in storage devices 406.Storage server 502 may, for example, be a NAS server. The storage server502 includes operating system 504 that, for example, manages thesoftware processes and/or services executing on the storage server. Forexample, operating system 504 may implement a write anywhere file system514 that organizes data stored in storage devices 406 as a hierarchicalstructure of named directories and files.

As shown in FIG. 5, operating system 504 may support a variety ofsoftware layers 506, 508, 510, 512, 514, and 516 organized to form amufti-protocol engine that provides data paths for client computingdevices 402 to access data stored in storage devices 406. The RedundantArray of Independent Disks (RAID) layer 516 provides the interface toRAID controllers. In general, a RAID controller can distribute data thatstorage server 502 writes to a virtual hard disk over several storagedevices 406. The file system 514 forms an intermediate layer betweenstorage devices 406 and software applications. It should be appreciatedthat storage devices 406 may be block-oriented storage medias and filesystem 514 is configured to manage the blocks used by the storagedevices. In addition, file system 514 provides client computing devices402 access to data organized in blocks by way of example directories andfiles. The NFS layer 506, CIFS layer 520, and iSCSI layer 512 providesupport for NFS, CIFS and iSCSI protocols, respectively. Additionallyincluded is application layer 508 that interfaces to and performs commonapplication services for application processes, such as backup andrecovery software, data retention software, and other softwareapplications.

FIG. 6 depicts a flow diagram of detailed methods, in accordance with anexample embodiment, for modeling a storage environment. In an exampleembodiment, method 600 may be implemented by storage system analyticsmodule 203 of FIG. 2 and employed in computing device 202. Initially, astorage environment to be modeled is defined. To define a storageenvironment, a user may specify the various components included withinthe storage environment and the functional relationships between thecomponents. The user may also define the functional relationshipsbetween the components. Alternatively, a program application mayautomatically detect the various components (and their functionalrelationships) within a storage environment. These detected components(and their relationships) define the storage environment. This definedstorage environment is comprised of a variety of components and eachcomponent may be simulated by one or more component models, which may bestored in a library module. As depicted in FIG. 6, component modelsassociated with the defined storage environment are selected from thelibrary module at 602.

Each component model may define a resource needed by the componentmodel. A resource is an input and/or support needed by the componentmodel to function. An example of a resource is an input variable or dataneeded by a component model to make a particular calculation. In anotherexample, a component model may need support component models tofunction. The resources are the support component models. As an example,an operating system needs to be hosted on a computing device, such as astorage server. Accordingly, a component model that simulates anoperating system may define a computing device as a needed resource. At604, component models from the library module that provide the resourcesare identified and loaded (or retrieved) from the library module at 606.

A system model is then composed from the loaded component models at 608.The component models when combined simulate the defined storageenvironment. As explained in more detail below, the composition of thesystem model may include associating the component models with eachother based on the functional relationships defined by the componentmodels.

Still referring to FIG. 6, a representation of the system model may thenbe constructed at 610. In an example, the structure of the composedsystem model may be in the form of or resemble a directed graph.Accordingly, the system model may be represented as a directed graph. Asexplained in more detail below, the directed graph may depict thecomponent models and the functional relationships between the componentmodels. A simulated workload may then be applied to the system model at612 and, as explained in more detail below, the directed graph can beconfigured to define the impact of the simulated workload on the storageenvironment.

FIG. 7 depicts a flow diagram of detailed methods, in accordance with anexample embodiment, for composing a system model from component models.In an example embodiment, method 700 may be implemented by storagesystem analytics module 203 of FIG. 2 and employed in computing device202. Here, a storage environment to be modeled is initially defined.This defined storage environment is comprised of a variety of componentsand each of the components may be simulated by one or more componentmodels, which are stored in a library module. As depicted in FIG. 7, acomponent model associated with the defined storage environment isloaded from a library module at 702. The component model may include ordefine one or more functional relationships with other component modelsand the functional relationships are identified from the component modelat 704. Generally, a functional relationship describes a connection orassociation of a component model with another component model. Forexample, a functional relationship may define that a component model isin communication with another component model. In this example, thefunctional relationship may further define that an input of thecomponent model is in communication with an output of another componentmodel or vice versa. In another example, the functional relationship mayalso define that the component model provides its service by making useof the service provided by one or more component models.

In addition to the functional relationships, each component model maydefine one or more needed resources, which are also identified from thecomponent model at 704. The resources needed by the component model arethen loaded (or retrieved) from the library module at 708. As discussedabove, the library module is a data structure that is configured tostore component models. The component models are loaded by transferringthe component models from the library to the system model. Adetermination is made at 709 whether the component model loaded is thelast component model associated with the storage environment. If thereare additional component models associated with the storage environment,then another component model associated with the storage environment isidentified at 712 and this component model is loaded at 702. The methodsrepeat until all the component models associated with the storageenvironment are loaded.

If a determination is made that the component model is the lastcomponent model associated with the storage environment (or that all thecomponent models have been loaded), then the component models areassociated with each other at 710 based on the functional relationships.The determination may be made by identifying whether all the componentmodels associated with the storage environment have been loaded. Anexample of the determination may include comparing the particularcomponent model against a list of loaded component models. The componentmodels may then be associated by, for example, connecting the componentmodels together according to the defined functional relationships. Itshould be appreciated that the associations do not need to be made onceall the component models are loaded into the system model. In anotherembodiment, the associations can be made when each component model isloaded into the system model. Since the associations are made as eachcomponent model is loaded, the system model is complete once the lastcomponent model associated with the storage environment is loaded.

FIG. 8 depicts another directed graph representation of a system model800, in accordance with an example embodiment. The structure of thecomposed system model 800 may be in the form of or resemble a directedgraph. Accordingly, a representation of system model 800 may beconstructed with a directed graph. In effect, composed system model 800can be represented by a directed graph. As depicted in FIG. 8, adirected graph of an example system model 800 defines component modelsrepresented as nodes and functional relationships between the componentmodels that are represented as lines or edges between the componentmodels.

The directed graph shows that system model 800 includes softwarecomponents such as email messaging software 802, file caching software804, and backup software 806. The nodes represent the component modelsthat simulate the software components. The system model 800 alsoincludes hardware component models that simulate storage server 808 andstorage devices 810 and 811. Generally, the email messaging softwarehosts emails and makes the emails available or accessible to otherclient software by way of, for example, Post Office Protocol version 3(POP3) or Internet Message Access Protocol (IMAP). The file cachingsoftware, which is in communication with email messaging software andassociated with storage server, implements file caching by automaticallyreplicating, storing, and serving data requested over, for example, NFS.Backup software 806, which is associated with storage server 808,backups data in the storage environment by mirroring the data to one ormore storage devices.

In an example embodiment, the directed graph (or other representationsof system model 800) may be provided in a graphical user interface. Auser may interact with the directed graph through the graphical userinterface. Examples of interactions may include moving the componentmodels, connecting component models, adding component models, applyingsimulated workloads, and other user interactions. It should be notedthat any suitable number of suitable layouts can be designed forgraphical depiction of system model 800, as FIG. 8 (and FIG. 1) does notrepresent all possible layout options available. The displayableappearance of the regions (e.g., regions representing component models)can be defined by any suitable geometric shape, alphanumeric character,symbol, shading, pattern, and color. Furthermore, the computing devicesthat provide the graphical user interface may have a fixed set oflayouts, utilize a defined protocol or language to define a layout, oran external structure can be reported to the computing device thatdefines a layout.

Still referring to FIG. 8, a simulated workload 820 may be applied tothe system model, and the directed graph can visually define the impactof the simulated workload on the storage environment. For example,simulated workload 820 (e.g., a number of emails) is applied to thecomponent model of email messaging software 802. The directed graph mayillustrate the simulated impact of simulated workload 820 on the storageenvironment. For example, directed graph illustrates that simulatedworkload 820 results in data being transferred to both component modelsof storage devices 810 and 811, which is illustrated by the two arrowspointing from storage server 808 to storage devices 810. If simulatedworkload 820 is reduced, for example, the directed graph mayalternatively illustrate that data is transferred to only one storagedevice 810 or 811, which can be illustrated by one arrow pointing fromstorage server 808 to one of the storage devices. Accordingly, thedirected graph can be used to illustrate the simulated behavior of astorage environment when, for example, subjected to various simulatedworkloads. A user may therefore analyze the simulated impacts tohardware and software components as well as to the underlyingarchitecture of the storage environment with various hypotheticalchanges to simulated workloads. For example, a user may use suchsimulated impact information to troubleshoot the storage environmentwithout access to or testing on an actual storage environment. The usermay also use such simulated impact information to design a storageenvironment.

FIG. 9 depicts a simplified block diagram of a machine in the exampleform of a computing system within which a set of instructions, forcausing the machine to perform any one or more of the methodologiesdiscussed herein, may be executed. Computing system 900 may also bereferred to as a computing device and, as used herein, the terms“computing system” and “computing device” may be used interchangeably.In alternative embodiments, the machine may be connected (e.g.,networked) to other machines. In a networked deployment, the machine mayoperate in the capacity of a server or a client machine in client-servernetwork environment, or as a peer machine in a peer-to-peer (ordistributed) network environment. The machine may be a personal computer(PC), a tablet PC, a Personal Digital Assistant (PDA), a web applianceor any machine capable of executing a set of instructions (sequential orotherwise) that specify actions to be taken by that machine. Further,while only a single machine is illustrated, the term “machine” shallalso be taken to include any collection of machines that individually orjointly execute a set (or multiple sets) of instructions to perform anyone or more of the methodologies discussed herein.

Example computing system 900 includes processor 902 (e.g., a centralprocessing unit (CPU), a graphics processing unit (GPU) or both), mainmemory 904 and static memory 906, which communicate with each other viabus 908. Computing system 900 may further include video display unit 910(e.g., a plasma display, a liquid crystal display (LCD) or a cathode raytube (CRT)). Computing system 900 also includes alphanumeric inputdevice 912 (e.g., a keyboard), user interface (UI) navigation device 914(e.g., a mouse), disk drive unit 916, signal generation device 918(e.g., a speaker) and network interface device 920.

Disk drive unit 916 includes machine-readable medium 922 on which isstored one or more sets of instructions and data structures (e.g.,software 924) embodying or utilized by any one or more of themethodologies or functions described herein. Software 924 may alsoreside, completely or at least partially, within main memory 904 and/orwithin processor 902 during execution thereof by computing system 900,with main memory 904 and processor 902 also constitutingmachine-readable, tangible media. Software 924 may further betransmitted or received over network 926 via network interface device920 utilizing any one of a number of well-known transfer protocols(e.g., Hypertext Transfer Protocol (HTTP)).

While machine-readable medium 922 is shown in an example embodiment tobe a single medium, the term “machine-readable medium” should be takento include a single medium or multiple media (e.g., a centralized ordistributed database, and/or associated caches) that store the one ormore sets of instructions. The term “machine-readable medium” shall alsobe taken to include any medium that is capable of storing, encoding orcarrying a set of instructions for execution by the machine and thatcause the machine to perform any one or more of the methodologies of thepresent application, or that is capable of storing, encoding or carryingdata structures utilized by or associated with such a set ofinstructions. The term “machine-readable medium” shall accordingly betaken to include, but not be limited to, solid-state memories, opticaland magnetic media, and carrier wave signals.

While the invention(s) is (are) described with reference to variousimplementations and exploitations, it will be understood that theseembodiments are illustrative and that the scope of the invention(s) isnot limited to them. In general, techniques for modeling storageenvironments may be implemented with facilities consistent with anyhardware system or hardware systems defined herein. Many variations,modifications, additions, and improvements are possible.

Plural instances may be provided for components, operations orstructures described herein as a single instance. Finally, boundariesbetween various components, operations, and data stores are somewhatarbitrary, and particular operations are illustrated in the context ofspecific illustrative configurations. Other allocations of functionalityare envisioned and may fall within the scope of the invention(s). Ingeneral, structures and functionality presented as separate componentsin the exemplary configurations may be implemented as a combinedstructure or component. Similarly, structures and functionalitypresented as a single component may be implemented as separatecomponents. These and other variations, modifications, additions, andimprovements fall within the scope of the invention(s).

What is claimed is:
 1. A method of modeling a storage environment havinga component, the method comprising: loading a component model that isconfigured to simulate the component of the storage environment;composing a system model from the component model, the system modelconfigured to simulate the storage environment; and applying a simulatedworkload to the system model, the system model configured to simulate animpact of the simulated workload on the storage environment.